[north]

Just hit the MPC, 67 was quite the year for air cleaners at Pontiac! Well over 30 different part numbers for air cleaner assemblies and that’s just for 4 bbl’s!

Restricting things to just B bodies cuts it down to 10. What creates so many variations this year is the factors of having a closed crankcase set up or not, having a smog pump or not (you could have closed crank case or not without a smog pump but all smog pump cars had the closed crankcase vent set up) along with HD filter or not and engine variety. They cleaned things up big time in 68, from about 35 to 5!

So for big cars only (remember that air cleaner assemblies were sold complete with lid and air filter element.;

400 4bbl with no smog pump and no closed crankcase system you had 6420972 for the standard air filter and 6422849 for the HD oiled filter element.
(These we’re carry over from 1966)

400 4bbl with no smog pump but with closed crankcase system you had 6423212 for standard and 6423213 for HD filter. (These we’re new for 67)

Next was 400 4bbl with smog pump (and closed crank vent), 6484472 for standard filter and 6424505 for HD filter. These were also new for 67.

Next is 428 (not HO, not 2+2, no closed crankcase), 6423207. Then 6422168 is same application but for the 2+2, chrome plated (Also 6422168 is the same number as the non HO non smog GTO). Both are new numbers for 67 but the chrome one has a number that indicates 66 vintage but the exact number is not used previously.

Next comes 6484473 which is for all 428’s (HO and non HO) with smog pump and or closed crankcase. No mention of chrome or not but price would indicate yes and as mentioned all 428’s were supposed to have chrome dress. These are new for 67 numbers.

Lastly is 428 HO without smog pump or closed crankcase, 6424590. same part number as 400HO GTO with the same lack of smog pump or closed crank. Again, a new for 67 number.

Note that no HD filter options were offered on any 428’s.

I think it breaks down like this visually…

All 400 4bbls used black closed small diameter snorkel lids

Non smog 2+2 (except HO) used the GTO 4bbl chrome pancake style air cleaner.

All non smog, non closed crank case 428 HO’s used the open element closed lid air cleaner.

All other 428’s (with smog or closed crank) used a larger diameter snorkel chrome lid air cleaner.